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CarCareTruth

Sodium Benzoate

  • Corrosion inhibitors
  • CAS 532-32-1
  • IUPAC: Sodium benzoate

CarCareTruth tracks Sodium Benzoate (CAS 532-32-1) as a car-care ingredient. It is readily biodegradable.

FDA GRAS (Generally Recognized as Safe) as a food preservative. LD50 oral rat 4,070 mg/kg. At 1.5–5% in coolant, does not contribute an additional H-code classification beyond the ethylene glycol baseline.

Sodium benzoate is the sodium salt of benzoic acid, widely used as a food preservative and antimicrobial agent (FDA GRAS). In automotive coolant formulations, it serves as a corrosion inhibitor, particularly protecting aluminum surfaces in modern engine cooling systems. Its broad-spectrum antimicrobial properties also help prevent microbiological contamination of coolant systems.

At the concentrations used in consumer antifreeze products (1.5–5%), sodium benzoate does not carry a GHS hazard classification. The compound is readily biodegradable and has low aquatic toxicity (LC50 fish 484 mg/L at 96h, which is above the H400 threshold of 1 mg/L and H413 threshold of 10 mg/L for long-term classification, so no H4xx classification applies). The compound's inclusion in coolant poses no environmental classification concern at product-level concentrations.

Health & environment profile

VOC
no
Prop 65 listed
no
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
no
Biodegradable
yes
Bioaccumulative
no
Persistent
no
Ozone depleting
no
Microplastic
no
PFAS
no
Env. score
3/5
Purpose: Corrosion inhibitor and antimicrobial agent in coolant formulations; protects aluminum and ferrous metals

Common questions about Sodium Benzoate

What is Sodium Benzoate used for in car care?
Corrosion inhibitor and antimicrobial agent in coolant formulations; protects aluminum and ferrous metals
Is Sodium Benzoate a VOC?
No. Sodium Benzoate is not classified as a volatile organic compound (VOC).
Is Sodium Benzoate on California's Proposition 65 list?
No. Sodium Benzoate is not on California's Proposition 65 list.
Is Sodium Benzoate biodegradable?
Yes. Sodium Benzoate has a confirmed biodegradable profile.

No products on file contain this (yet)

Related

Health and environment notes translate the manufacturer Safety Data Sheet, the GHS classification, and authoritative regulatory listings (California Prop 65, EPA). Not medical advice. They describe the ingredient itself; whether a hazard applies to a finished product depends on its concentration and how it's used.